The issue is related to a race condition in the `dmam free coherent()` function, which can lead to data corruption and crashes. This occurs when a concurrent task makes an allocation with the same `vaddr` and adds it to the devres list between the time `dmam free coherent()` frees a DMA allocation and calls `devres destroy()` to remove and free the data structure used to track the DMA allocation. As a result, there can be two entries in the devres list with the same `vaddr`, and `devres destroy()` can free the wrong entry, triggering the `WARN ON()` in `dmam match`. The fix involves destroying the devres entry before freeing the DMA allocation.